Mobile ad hoc networks may exhibit unidirectional links due to the nature of wireless communication. Presence of unidirectional links interferes with the control flow of many existing unicast routing protocols for such networks, which adversely effects their performance and limits their applicability. In this paper, we present a new protocol designed to support unicast routing over both bidirectional and unidirectional links in ad hoc networks, while preserving low bandwidth utilization and providing faster and more reliable packet delivery. The WAR (Witness-Aided Routing) protocol is based on the concept of witness host, whose role is to help in bypassing a unidirectional or a failed link along the path. We present a preliminary analysis to compare the expected performance of WAR with the Dynamic Source Routing (DSR) protocol.